Latex一次添加两个图（并列），半栏

\begin{figure}[t]
\centering
\includegraphics[width=0.9\columnwidth, clip=true, trim=0 0 0 32]{figures/freq-non-merge.pdf}
\includegraphics[width=0.9\columnwidth, clip=true, trim=0 0 0 0]{figures/freq-merge.pdf}
\caption{Commit frequency before and after the \Tvis adoption.}\vspace{-0.4cm}
\label{fig:freq}
\end{figure}

如图：